Home clothes washing machines must either keep the lid locked in a closed position during the spin dry cycle to prevent access to the rapidly rotating basket in the machine that contains the materials which are being laundered or the motor driving the basket must be braked and stopped as soon as anyone begins to open the lid.
For the latter, it is necessary to provide a switch which changes state immediately upon initiating opening of the lid. The switch causes instantaneous de-energization of the motor and activation of an electrically controlled brake. Switches which have been used, of course, have their contacts enclosed in a housing to prevent the contacts and any electrically energized parts or insulating surfaces from being contaminated by electrically conductive detergent suds or spray or even by moisture which is prevalent in the high humidity ambient within the housing of a washing machine. A variety of switches have been designed with the intention of prohibiting entry into the switch housing of the conductive liquids which are present in the washing machine. Conventional switches typically have a movable plunger extending from the inside of the switch housing to the outside. The plunger is typically spring biased so it will cause the switch contacts in the housing to open when the force of the lid which holds the plunger depressed is removed. Switch actuators in the form of plungers and the like traditionally move linearly and act somewhat like a pump piston which results in aspirating humid air and liquid into the switch housing each time the plunger is depressed inwardly or is restored outwardly
Problems of sealing the switch housing have been encountered in the design of lid operated switches. The switch housing cannot be made in one piece so a good seal is required between the parts of a two part housing. There are possible leakage paths along the electrical conductors which necessarily pass into the housing to connect with the contacts in the housing.
The new lid switch disclosed herein provides a solution to the foregoing problems. It is characterized as not being susceptible to damage by hot water, cold water, wetting agents, bleach, detergents and humid conditions found under the lid of a washing machine.